bokeh.models.mappers

Models for mapping values from one range or space to another.

class CategoricalColorMapper(**kwargs)[source]

Bases: bokeh.models.mappers.ColorMapper

Map categories to colors. Values that are passed to this mapper that aren’t in factors will be assigned the nan_color.

end

property type: Int

A start index to “slice” data factors with before color mapping.

For example, if the data to color map consists of 2-level factors such as ["2016", "sales"] and ["2017", "marketing"], then setting end=1 will perform color mapping only based on the first sub-factor (i.e. in this case based on the year "2016" or "2017")

If None then all sub-factors from start to the end of the factor will be used for color mapping.

factors

property type: Either ( Seq ( String ), Seq ( Tuple ( String , String ) ), Seq ( Tuple ( String , String , String ) ) )

A sequence of factors / categories that map to the color palette. For example the following color mapper:

mapper = CategoricalColorMapper(palette=["red", "blue"], factors=["foo", "bar"])

will map the factor "foo" to red and the factor "bar" to blue.

start

property type: Int

A start index to “slice” data factors with before color mapping.

For example, if the data to color map consists of 2-level factors such as ["2016", "sales"] and ["2016", "marketing"], then setting start=1 will perform color mapping only based on the second sub-factor (i.e. in this case based on the department "sales" or "marketing")

JSON Prototype
{
  "end": null,
  "factors": null,
  "id": "62002299-c566-4f25-af94-5470bc68f946",
  "js_event_callbacks": {},
  "js_property_callbacks": {},
  "name": null,
  "nan_color": "gray",
  "palette": null,
  "start": 0,
  "subscribed_events": [],
  "tags": []
}
class ColorMapper(palette=None, **kwargs)[source]

Bases: bokeh.models.transforms.Transform

Base class for color mapper types.

Note

This is an abstract base class used to help organize the hierarchy of Bokeh model types. It is not useful to instantiate on its own.

nan_color

property type: Color

Color to be used if data is NaN. Default: ‘gray’

palette

property type: Seq ( Color )

A sequence of colors to use as the target palette for mapping.

This property can also be set as a String, to the name of any of the palettes shown in bokeh.palettes.

JSON Prototype
{
  "id": "0a46bdab-3676-4751-92bc-2d8261d278ed",
  "js_event_callbacks": {},
  "js_property_callbacks": {},
  "name": null,
  "nan_color": "gray",
  "palette": null,
  "subscribed_events": [],
  "tags": []
}
class ContinuousColorMapper(palette=None, **kwargs)[source]

Bases: bokeh.models.mappers.ColorMapper

Base class for continuous color mapper types.

Note

This is an abstract base class used to help organize the hierarchy of Bokeh model types. It is not useful to instantiate on its own.

high

property type: Float

The maximum value of the range to map into the palette. Values above this are clamped to high.

high_color

property type: Color

Color to be used if data is higher than high value. If None, values higher than high are mapped to the last color in the palette.

low

property type: Float

The minimum value of the range to map into the palette. Values below this are clamped to low.

low_color

property type: Color

Color to be used if data is lower than low value. If None, values lower than low are mapped to the first color in the palette.

JSON Prototype
{
  "high": null,
  "high_color": null,
  "id": "e395975b-ff6d-4ecd-bfc7-d17f525ff7b7",
  "js_event_callbacks": {},
  "js_property_callbacks": {},
  "low": null,
  "low_color": null,
  "name": null,
  "nan_color": "gray",
  "palette": null,
  "subscribed_events": [],
  "tags": []
}
class LinearColorMapper(palette=None, **kwargs)[source]

Bases: bokeh.models.mappers.ContinuousColorMapper

Map numbers in a range [low, high] linearly into a sequence of colors (a palette).

For example, if the range is [0, 99] and the palette is ['red', 'green', 'blue'], the values would be mapped as follows:

      x < 0  : 'red'     # values < low are clamped
 0 >= x < 33 : 'red'
33 >= x < 66 : 'green'
66 >= x < 99 : 'blue'
99 >= x      : 'blue'    # values > high are clamped
JSON Prototype
{
  "high": null,
  "high_color": null,
  "id": "5fff4885-ae02-4281-b167-9a80f63f9067",
  "js_event_callbacks": {},
  "js_property_callbacks": {},
  "low": null,
  "low_color": null,
  "name": null,
  "nan_color": "gray",
  "palette": null,
  "subscribed_events": [],
  "tags": []
}
class LogColorMapper(palette=None, **kwargs)[source]

Bases: bokeh.models.mappers.ContinuousColorMapper

Map numbers in a range [low, high] into a sequence of colors (a palette) on a natural logarithm scale.

For example, if the range is [0, 25] and the palette is ['red', 'green', 'blue'], the values would be mapped as follows:

         x < 0     : 'red'     # values < low are clamped
0     >= x < 2.72  : 'red'     # math.e ** 1
2.72  >= x < 7.39  : 'green'   # math.e ** 2
7.39  >= x < 20.09 : 'blue'    # math.e ** 3
20.09 >= x         : 'blue'    # values > high are clamped

Warning

The LogColorMapper only works for images with scalar values that are non-negative.

JSON Prototype
{
  "high": null,
  "high_color": null,
  "id": "bb955313-4300-43ba-8e2c-c053e900338f",
  "js_event_callbacks": {},
  "js_property_callbacks": {},
  "low": null,
  "low_color": null,
  "name": null,
  "nan_color": "gray",
  "palette": null,
  "subscribed_events": [],
  "tags": []
}